Good Champions to Climb with in general?

So we're slowly reaching our conclusion of our 6th season, which is also my first one. I really want to get to gold this year, but I've been hovering around Silver 3 and Silver 2 for quite some time. I can't seem to get out of it. So, people are good with champs that they play for a while, as well as getting some practice into one. After all, everyone has a different level of skill and performance for each champion. However, I'm pretty desperate to climb out. Besides the poor solution of boosting (not looking at cause why spend $50+ on it), are there any good champions that are doing pretty well right now? And are the champions I select themselves tip some scale? These are the champs I pick the most often. Feel free to criticize my questions above, since overall, this is a skill thing (Im also not going to blame my team, since it's my fault some of the time)

Mid: I main her, and usually perform well ingame, but I usually don't get mid often, and I also don't do so much if the tanky enemy jg or top laner gets fed. Adc: . I have the 2nd most mastery points and most games on Cait and usually win lane. As for Luc, I'm not the best at him, as I have a bad laning phase with him and strongly rely on my support. Supports: Nami is my best support, and I (to my memory) almost always win lane with her. The only problem is that (me personally) the ult feels a bit lack-luster if your team doesn't follow up to well. Sona is great at poking, but if I lose lane, I feel pretty much useless. Lastly Bard. Love this guy, but I lose quite often with him. I don't know if I play him to well or not, but I don't feel my presence to much unless the jg'er ganks and in teamfights.